Playwrights Jon Robin Baitz ("Hedda Gabbler"), John Guare ("Sweet Smell of Success"), Peter Parnell ("Q.E.D."), and directors Gene Saks ("Mr. Goldwyn"), Daniel Sullivan ("Proof"), and Mary Zimmerman ("Metamorphoses") discuss their approaches to writing, directing, and adaptations; the collaboration process with directors, writers, producers, sets, and actors; reactions to a production's first preview; and the source of ideas for playwrights.